Input Apparatus Having an Input Recognition Unit and Input Recognition Method by Using the Same

1. An input apparatus, comprising: an infrared camera; an image capture unit configured to sequentially capture a plurality of temperature distribution images photographed at predetermined time intervals by the infrared camera; and an input recognition unit configured to detect, from among the plurality of temperature distribution images captured by the image capture unit, pairs of skin temperature image portions each corresponding to a temperature of skin of a person, to recognize, from among the pairs of skin temperature image portions detected, pairs of skin temperature image portions as pairs of detection target images, from among which motions are observed, and to recognize an operation input based on states of the motions of the pairs of detection target images, wherein the input recognition unit is configured to detect the pairs of skin temperature image portions from among the plurality of temperature distribution images by comparing temperature values of pixels of each of the plurality of temperature distribution images with each other with respect to a first threshold and a second threshold which are set to define a temperature range of the skin of the person, and wherein the input recognition unit is further configured to generate a pair of binary images each containing the pairs of skin temperature image portions by binarizing the plurality of temperature distribution images based on whether or not the temperature values of the pixels of each of the plurality of temperature distribution images fall within the temperature range defined by the first threshold and the second threshold, generate a difference image of the pairs of detection target images in the pairs of skin temperature image portions, from among which the motions are observed, by determining a difference between the pair of binary images of the plurality of temperature distribution images, and judge, by using the difference image, the states of the motions of the pairs of detection target images.

2. The input apparatus according to claim 1 , wherein the input recognition unit is further configured to erase image parts corresponding to the pairs of skin temperature image portions in each of which the motion has been judged to be different from the difference image to obtain a detection target image.

3. The input apparatus according to claim 2 , wherein the input recognition unit is further configured to calculate a position of a feature point of the pairs of detection target images based on the difference image, and judge a state of a motion of the pairs of detection target images based on variation of the position of the feature point.

4. The input apparatus according to claim 1 , wherein the predetermined time interval includes one frame interval of a photographing operation of the infrared camera.

5. The input apparatus according to claim 1 , wherein the input recognition unit is further configured to select a detection target image based on which of the pairs of skin temperature image portions occupies an area equal to or larger than a predetermined area.

6. The input apparatus according to claim 1 , wherein the input recognition unit executes a recognition process of the operation input provided that a positional variation by a predetermined amount or larger, which shows at least one of the states of the motions of the pairs of detection target images, is detected predetermined times or more.

7. The input apparatus according to claim 1 , wherein the input recognition unit is further configured to detect the pairs of skin temperature image portions from among the plurality of temperature distribution images by comparing the temperature values of the pixels of each of the plurality of temperature distribution images with each other with respect to the first threshold and the second threshold which are set to define the temperature range of the skin of the person, and after that, set a third threshold and a fourth threshold which are set to define a temperature range smaller than the temperature range defined by the first threshold and the second threshold based on the temperature values of the pairs of skin temperature image portions recognized as the pairs of detection target images, and detect subsequent pairs of skin temperature image portions from among the plurality of temperature distribution images by using the third threshold and the fourth threshold.

8. The input apparatus according to claim 1 , wherein, in a case where a particular motion has been detected from among the pairs of detection target images, the input recognition unit is configured to set a detection target range based on image positions of the pairs of detection target images in a middle of showing the particular motion, and detect subsequent pairs of skin temperature image portions from the detection target range.

9. The input apparatus according to claim 1 , wherein the input recognition unit is configured to execute a process of outputting a message in a case where the pairs of skin temperature image portions, from among which a motion is observed with reference to the difference image, have not been detected within a predetermined time period.

10. The input apparatus according to claim 1 , wherein, in a case where a plurality of detection target images have been obtained, the input recognition unit is configured to select one detection target image from among the plurality of detection target images, set a detection condition corresponding to the selected one detection target image, and detect subsequent detection target images based on the detection condition.

11. The input apparatus according to claim 10 , wherein the detection condition includes at least one of a condition of a temperature range which has been set in accordance with a temperature of the selected one detection target image, and a condition of a detection target range which has been set based on an image position of the selected one detection target image.

12. The input apparatus according to claim 10 , wherein in the case where a plurality of detection target images have been obtained, the input recognition unit selects, from among the plurality of detection target images, an image corresponding to a particular motion as one detection target image.

13. The input apparatus according to claim 1 , further comprising an apparatus control unit configured to effectively control in response to the operation input recognized by the input recognition unit.

14. An input recognition method, comprising: sequentially capturing a plurality of temperature distribution images photographed at predetermined time intervals by an infrared camera; detecting, from among the plurality of temperature distribution images thus captured, pairs of skin temperature image portions each corresponding to a temperature of skin of a person; recognizing, from among the pairs of skin temperature image portions thus detected, pairs of skin temperature image portions as pairs of detection target images, from among which motions are observed; and recognizing an operation input based on states of the motions of the pairs of detection target images, in a case where a particular motion has been detected from among the pairs of detection target images, further comprising: setting a detection target range based on image positions of the pairs of detection target images in a middle of showing the particular motion, and detecting subsequent pairs of skin temperature image portions from the detection target range.

15. An input apparatus, comprising: an infrared camera; an image capture unit configured to sequentially capture a plurality of temperature distribution images photographed at predetermined time intervals by the infrared camera; and an input recognition unit configured to detect, from among the plurality of temperature distribution images captured by the image capture unit, pairs of skin temperature image portions each corresponding to a temperature of skin of a person, to recognize, from among the pairs of skin temperature image portions detected, pairs of skin temperature image portions as pairs of detection target images, from among which motions are observed, and to recognize an operation input based on states of the motions of the pairs of detection target images, wherein the input recognition unit is further configured to detect the pairs of skin temperature image portions from among the plurality of temperature distribution images by comparing the temperature values of the pixels of each of the plurality of temperature distribution images with each other with respect to the first threshold and the second threshold which are set to define the temperature range of the skin of the person, and after that, set a third threshold and a fourth threshold which are set to define a temperature range smaller than the temperature range defined by the first threshold and the second threshold based on the temperature values of the pairs of skin temperature image portions recognized as the pairs of detection target images, and detect subsequent pairs of skin temperature image portions from among the plurality of temperature distribution images by using the third threshold and the fourth threshold.

16. An input apparatus, comprising: an infrared camera; an image capture unit configured to sequentially capture a plurality of temperature distribution images photographed at predetermined time intervals by the infrared camera; and an input recognition unit configured to detect, from among the plurality of temperature distribution images captured by the image capture unit, pairs of skin temperature image portions each corresponding to a temperature of skin of a person, to recognize, from among the pairs of skin temperature image portions detected, pairs of skin temperature image portions as pairs of detection target images, from among which motions are observed, and to recognize an operation input based on states of the motions of the pairs of detection target images, wherein, in a case where a particular motion has been detected from among the pairs of detection target images, the input recognition unit is configured to set a detection target range based on image positions of the pairs of detection target images in a middle of showing the particular motion, and detect subsequent pairs of skin temperature image portions from the detection target range.

17. An input apparatus, comprising: an infrared camera; an image capture unit configured to sequentially capture a plurality of temperature distribution images photographed at predetermined time intervals by the infrared camera; and an input recognition unit configured to detect, from among the plurality of temperature distribution images captured by the image capture unit, pairs of skin temperature image portions each corresponding to a temperature of skin of a person, to recognize, from among the pairs of skin temperature image portions detected, pairs of skin temperature image portions as pairs of detection target images, from among which motions are observed, and to recognize an operation input based on states of the motions of the pairs of detection target images, wherein, in a case where a plurality of detection target images have been obtained, the input recognition unit is configured to select one detection target image from among the plurality of detection target images, set a detection condition corresponding to the selected one detection target image, and detect subsequent detection target images based on the detection condition.